Full blood
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
A term of relation, denoting descent from the same couple. Brothers and sisters of full blood are those who are bam of the same father and mother, or, as Justinian calls them, "ex utroque parente conjuncti."
Nov. 118, cc. 2, 3; Mackeld. Rom. Law, § 145.
The more usual term in modern law is "whole blood," (q. v.)